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To set the valves, I was just going to disconnect them all, set the engine up exactly as you mentioned at either TCD or BDC, apply some air, and then close both inlet and exhaust valves on one side, open the inlet fully on the other side, and adjust the exhaust til it's just closed by listening to the air passing through. Then disconnect that exhaust valve, open it, and adjust the inlet till it's just closed. Then repeat for the other side's valves. This should set the timing pretty well from the get-go.